Lung imaging has historically been dominated by conventional x-ray technology. The most widespread imaging study in the US remains the chest x-ray, with an estimated 100 million or more performed each year. Computerized tomography also delineates lung anatomy and pathology well. However, neither of these imaging techniques provides any significant insight into lung function and pathophysiology. Functional imaging of the lungs has historically been the domain of nuclear medicine. Even magnetic resonance imaging, which has allowed spectacular functional imaging of the human brain has been difficult to apply in the lung. Recent work has shown that hyperpolarized 3He, which is not radioactive and which is chemically inert. can be used as an MRI contrast agent to image lung ventilation with 10-100 times higher contrast than with standard MR imaging. This technique can potentially be used to diagnose and monitor pulmonary embolism, chronic lung disease, pneumonia, and other conditions that limit lung ventilation with very low risk to the patient. Only slight cost increases over conventional MRI will be required as more efficient, high throughput 3He polarization methods are demonstrated. Science Research Laboratory (SRL) has developed a method for producing multiple liters of hyperpolarized 3He quickly, efficiently, and without potentially dangerous additives. Phase I research efforts were highly successful indicating a high probability of success in Phase II. PROPOSED COMMERCIAL APPLICATION: SRL helium polarization technique is the only technology that can produce the required quantities of clean hyperpolarized 3He in time scales useful for clinical applications (1-2 hours). Since MRI devices are present in essentially all large hospitals there is a enormous potential market for such a device. Once the technique is demonstrated, SRL will actively pursue additional funds to construct a clinical prototype and to commercialize this new polarization technology. SRL is pursuing non-medical applications of hyperpolarized 3He NMR spectroscopy as well.